A magazine-exposure model that mixes Klotz's (1973) dependent Bernoulli-trials model for nonsubscribers with a degenerate distribution for subscribers is proposed. Let X, = 1 if a person reads an issue of a particular magazine and 0 otherwise. Klotz's parameterization is Pr(X i = 1) = P. and Pr(X, = 1 I x'-I = 1) = Afor i = 1, ... , k. Using the Markov assumption he obtains the joint distribution of R =~f=2 Xi-IX" S =~f=l X" and T = XI + Xb of which we are interested in the marginal distribution of S, the total number of issues a person reads. It is expected that p will be low for nonsubscribers but high for subscribers, so this heterogeneity is modeled by mixing Klotz's Markov model with a point mass of magnitude It at the point S = k. Maximum likelihood estimates of p , A, and It are used to fit the Markov mixture model to 40 magazines from a large print-media survey. The proposed model is shown to give a much better fit to these data than the beta-binomial model, the most popular nonproprietary magazine model, and a generalization of the beta-binomial model. where°< OJ < 1 and hIis the indicator function. Danaher (1988b) showed that the MBBD usually gives a better fit to magazine ED's than the BBD, at the expense of an additional parameter.The BBD and MBBD work reasonably well in practice for magazine ED's (Chandon 1976;Danaher 1988b;Greene and Stock 1967;Metheringham 1964), although the BBD has been shown to overestimate odd-numbered exposures by Schreiber (1969) and Chandon (1976). In fact the BBD is the most popular nonproprietary magazine model in use (Leckenby and Kishi 1982b). Now express S as the sum of k indicator random variables; Xi = 1 if the ith issue of the magazine is read and°o therwise. Klotz (1973) defined Assuming the Markov property, Klotz developed a Markov model for Bernoulli trials with dependence. He derived the exact joint distribution of (R, S, T), where R =~f=2 Xi-lXi, S =~f=l Xi' and T = Xl + Xi; and thenused this distribution to model monthly rainfall in Madison, Wisconsin. The distribution of just S was derived by Gabriel (1959) using a different parameterization. Klotz (1972) also used (R, S, T) to model the dependency of sex on that of the previous child. Chandon (1976) mentioned but did not fully develop a Markov model for magazine ED's using Klotz's (1973) model. For magazine readership p is a measure of popularity and A is a measure of the dependency between successive trails. Sabavala andMorrison (1977, 1981) call Athe "loyalty rate." The parameters p and A are aggregate population parameters; that is, each person has the same p and A. However, the population is expected to be heterogeneous with respect to reading behavior, being divided into two groups. The first group is called nonsubscribers, who rarely or never read a particular magazine, and the second is called subscribers, who always read the magazine. The population tends to cluster into these two groups, in which case p < A (Klotz 1973). In Section 2 I allow for this heterogeneity by mixing a Markov model for nonsub...